Article-handling apparatus

ABSTRACT

This invention is basically an improvement on the sliding piston-type sensor used for example at 21 or at right-angle downward bends to deliver cigarettes from a horizontal overhead conveyor to a chute extending downwards to a packing machine. The sensor according to this invention is preferably pivoted and has a convex underneath surface so as to respond rapidly to a drop in the level of the cigarettes beneath it by sinking into the hollow formed in the surface of the cigarette stack.

ljnited States Patent [1 I1 3,625,34fi

[72] Inventor Alan Keith McCornbie [50] Field of Search 198/37, 40, London, England 44, 43, 52, 53-58, 65-68, 83 [21] Appl. No, 822,386 V 22 Filed May 7, 19 9 [56] References Cited [45] Patented Dec: 7, 1971 UNITED STATES PATENTS 8 Molms Machine PW Limited 3,472,358 10/1969 Poupin 198/44 m England 2,745,410 5/1956 Molins 198/37 1 Pnormes May 10, 1968 3,433,347 3/1969 Molins 193 37 [33] Great Britain [3] 22413/68; Pnmary Exammer--R1chard E. Aegerter Feb 2 9 9 Great Britain, No. Anomey-Craig, Al'llOIlClii & Hill 10,942/69 ARTICLE-HANDLING APPARATUS 12 Claims, 3 Drawing Figs.

us. (:1 198/37, 1 198/40, 198/44 Int. Cl ..B65g 43/00, 865g 43/08 ABSTRACT: This invention is basically an improvement on the sliding piston-type sensor used for example at 21 or at right-angle downward bends to deliver cigarettes from a horizontal overhead conveyor to a chute extending downwards to a packing machine. The sensor according to this invention is preferably pivoted and has a convex underneath surface so as to respond rapidly to a drop in the level of the cigarettes beneath it by sinking into the hollow formed in the surface of the cigarette stack.

ARTICLE-HANDLING APPARATUS British Pat. application No. 1952/66 (and also the equivalent French Pat. No. 1,509,322 describes a sensor in the form of a float 36 or 42 controlling the feed of cigarettes or other rodlike articles (for example cigarette filter rods) in stack formation on a conveyor in relation to which the articles lie transversely. The present invention is concerned with a new form of sensor.

A sensor according to one aspect of the present invention is pivotally mounted, preferably about an axis parallel to the rodlike articles, so as to swing upwards and downwards about its pivot axis in response to the pressure of the articles beneath it.

The bottom surface of the sensor is preferably convex as viewed in the direction of the articles. With this arrangement, the sensor tends to respond more sensitively and more reliably to the state of the articles beneath it in that, as we have observed, the upper surface of the articles (especially in the case of cigarettes and other similarly light rodlike articles, for example cigarette filter rods) tends to form a concave depression, especially in the case of a T-junction, when the rate of feed of the cigarettes away from the zone beneath the sensor exceeds the rate of supply to that zone. In other words, a sensor with a convex undersurface is more likely to fit snugly into the concave depression and therefore represent quickly the true state of the cigarettes beneath the sensor, by registering approximately with the bottom of the hollow, whereas a flat or concave sensor would tend to touch only at one point furthest from the pivot axis, at which point the level of the articles may be momentarily untypically high. Moreover, a convex sensor helps to ensure that the articles remain properly aligned; the formation of a hollow with a free surface (such as a flat or concave sensor may more readily permit) can result in the articles turning into skew positions.

A convex lower surface may, according to a second aspect of this invention, also usefully be provided even in the case of a bodily movable sensor such as the sensor floats 36 and 42 described in the previously mentioned prior patent application. However a preferred arrangement according to this invention has a pivoted sensor, as already mentioned. This facilitates the use of a rotary speed-regulating mechanism for regulating the conveyor speed, since the sensor can be pivoted by means of a spindle which forms the input to the rotary speed regulating mechanism. Moreover, the sensor can then form a fairly smooth continuation to a top wall which confines the upper surface of the stack as it approaches the sensor.

Examples of sensors according to this invention are shown in the accompanying drawings. In these drawings:

FIG. I is a side view showing particularly a T-junction with a sensor according to this invention;

FIG. 2 is a plan view of the sensor shown in FIG. I; and

FIG. 3 shows two different sensors incorporated in a flow merging system.

As shown in FIG. I of the accompanying drawings, the stack of cigarettes is fed to the left by a conveyor 11 to a T-junction which is completed by a continued horizontal stack 12, carried by a conveyor 13, and a vertical stack lying between side walls 14 and 15. The walls 14 and 15 constitute a chute down which the cigarettes are fed, for example to a packing machine. The conveyor 13 may carry the stack of cigarettes 12 towards a further chute or series of chutes feeding further packing machines. The conveyors l1 and 13 are in the form of endless conveyor bands, and they return round pulleys l6 and 17 as shown.

FIG. 1 is intended to show basically a T-junction, but it also shows in chain-dotted outline a convex end wall 18 which may be used to form a simple right-angle downward bend, that is to say a bend which feeds all the cigarettes from the stack 10 down the chute. In the case of a simple bend, it will be appreciated that the conveyor 13 and roller 17 would be omitted. As an alternative to the convex form shown, the wall 18 may be either flat or concave, depending upon the characteristics of the cigarettes being handled.

As shown particularly in FIG. 11, the sensor above the cigarettes at the T-junction or bend is in the form of a convex plate 19 which is secured at its upstream end (i.e. in relation to cigarette flow) to a cylindrical member 20. This member 20 is carried by a spindle 21 (see FIG. 2) which is rotatably mounted in a speed regulating mechanism 22 via ball bearings (not shown). The ball bearings enable the plate 19 to rotate very freely so that it can respond rapidly under its own weight, which must be low in order not to apply more than the minimum pressure to the cigarettes.

FIG. 1 shows the righthand end of the plate 19 with its bottom face just above the bottom face of a fixed top wall 23 confining the upper surface of the stack 10. However, the axis of the cylindrical member 20 is preferably very slightly lower so that the bottom surface of the plate is just below that of the wall 23; nevertheless it will be appreciated that the plate 19 forms a fairly smooth continuation of the top wall 23.

A fixed plate 24 serves partly as a top wall confining the upper surface of the stack 12 for a short distance from the T- junction, and is curved upwards towards its right-hand end so as to define a slightly converging channel for the stack 12 which helps to nest together the cigarettes of the stack 12. Also, as shown in FIG. 2, the right-hand end of the plate 24 has two slots, leaving three spaced legs 25, while the left-hand end of the sensor plate 19 has a single-central slot, leaving two spaced legs 26. The arrangement is such that the legs 26 of the plate 19 can pass through the slots between the legs 25 of the plate 24. Nevertheless the overlapping of the plates 24 and 19, as seen in FIG. 1, serves to prevent the escape of any cigarettes. As an alternative, the plate 19 may be unslotted, and the right-hand end portion of the plate 24 may be replaced by a plate which extends upwards and is curved about the axis of the cylindrical member 20 so that a fixed small clearance is maintained between that plate and the free end of the sensor plate 19.

The sensor plate 19 is shown in solid outline in FIG. 1 in approximately the middle of its range of movement, while chaindotted outlines show approximately the upper and lower limits of its movement. It will be seen that the area defined by the two chain dotted outlines and by the plate 24 is relatively small, that is to say represents a relatively small number of cigarettes. This is to be contrasted with the arrangement described in the previously mentioned prior patent application, in which displacement of the float sensor 36 or 42 in moving between its lowest and uppermost positions is deliberately substantial so as to constitute a reservoir.

In use, the sensor 19 controls the speed of the conveyor 11. That is to say, as the sensor I9 rises as a result of a buildup of cigarettes beneath it, the resultant clockwise rotation of the member 20 causes the mechanism 22 to reduce the speed of the electric motor driving the conveyor 11; conversely, a drop in the height of the cigarettes beneath the sensor 19 allows the sensor to drop and results in an increase in the speed of the motor-driving conveyor 11.

The mechanism 22 may be a known proprietary speed-regulating mechanism and preferably provides for stepless speed control. Adjustment can be achieved, in the example shown, by loosening a screw 27 and then moving a pointer 28 to any desired position along a dial 29, after which the screw is again tightened; movement of the pointer 28 in fact rotates the case of the mechanism 22.

The radius of curvature of the plate 19 may be smaller than that shown in the drawings.

The apparatus shown in FIG. 3 is a flow merging apparatus and embodies also an invention which is the subject of Pat. application No. 822,351 which corresponds fully to British Pat. application No. 224 l 3/68.

Referring to FIG. 3, cigarettes are fed in two continuous streams from cigarette reservoirs (not shown) of a construction similar to that shown in British Pat. No. 995,663. Each reservoir is of variable capacity so that it can accommodate different quantities of cigarettes while always remaining filled with cigarettes. This variation is achieved by means of a movable back wall supported on a carriage. For the purpose of the present apparatus a detector device 3 is mounted near the end of the travel of the carriage and is connected thereto by means of a line: it operates to determine the position of the carriage according to the length of line which is retracted or paid out. This enables the detector device 3 to give a signal indicating the capacity of the reservoir at any given moment. Alternatively the detector may comprise a contact sliding on an extended linear electrical resistance, in the manner of a rheostat; this resistance could be a series of small individual resistances.

The moving stacks of cigarettes A and B delivered from the reservoirs A, B are fed into a flow-merging apparatus which includes a movable flap plate 5 disposed between the streams A and B to meter the admission of the respective stacks A and B to a merger zone 33 according to the signals from the detectors 3.

Cigarettes are discharged from the flow-mixing apparatus in continuous stacks C and D which are fed respectively to two packing machines. Various modes of operation can be achieved: for example it is possible for cigarettes to be fed simultaneously from stack A to stack C and from stack B to stack D; and the respective rates of feed may vary, as will be further described. It is also possible for stack A or B to be stationary and for all the cigarettes from the other stack to be distributed between stacks C and D.

The stacks A and B are delivered in flow channels formed respectively by horizontal conveyors 6 and 7 with parallel top wall members 8 and 9 respectively. The conveyors 6 and 7 each comprise endless bands which run around rollers 10 and 11 respectively, a further deflecting roller 12 being provided for the conveyor 6.

Sensors 13 and 14 respectively for the stacks A and B are provided to bear on the incoming stacks and partly to confine the upper surfaces of the stacks. The speeds of the conveyors 6 and 7 are controlled automatically according to the positions of the respective sensor 13 or 14. Each sensor comprises a convex plate which rides on the cigarettes at the end of the band and is pivoted on a shaft 15 or 16 respectively which is connected to a rotary speed control device which controls the speed of the motor (not shown) driving the conveyor 6 or 7. Any deficiency of cigarettes in the stacks causes the sensors to drop, and the corresponding conveyor is speeded up to bring more cigarettes in to maintain the packing of the stack, while excessive pressure of cigarettes causes the control plate to rise and this displacement is used to slow down the corresponding conveyor to reduce the rate of supply of cigarettes. All this also helps to ensure that the channels defined by the conveyors 6 and 7 and top walls 8 and 9 are kept full, in other words the upper surface of the cigarette stacks are confined by the top wall members so that the heights of the stacks are well controlled.

The discharge stacks C and D from the flow-mixing apparatus are carried away on belt conveyors 18 and 19 respectively, beneath parallel top wall members 20 and 21 respectively. The conveyors 18 and 19 travel around rollers 22 and 23 and the lower run of the conveyor 18 is held clear of the lower stream D by means of a further roller 24. The speeds of movements of these conveyors are controlled by sensors in the region of the packing machinery which detect the demand for cigarettes and adjust the conveyor speeds to maintain the required flow.

A chute 17 extends downwards from the end of the conveyor 6 to feed the stack A to the merger zone 33. Between the end of the chute and the point where the stack C leaves the apparatus there is a further roller 25 which is rotated to assist in causing fluidization of the cigarette flow at this point.

The flap plate 5 is mounted between the streams A and B by means of support pins 26 and 28 of which the pins 26 are fixed and extend into slots 29 in the sides of the flap, while pins 28 are carried on the flap and run in horizontally arcuate slots 30 formed in side panels (not shown) which extend across both sides of the apparatus to contain the cigarettes against lengthwise movement. The flap plate 5 is rectangular in shape and has sufficient range of movement to enable it to close off the flow either from stream A or from stream B. A link arm 31 is connected externally of the apparatus to control the movement of the lower part of the flap plate 5 as the pins 28 run in the slots 30. This am is also used to set the position of the flap and this position is chosen according to the proportions of cigarettes available from A and B respectively. The flap is mounted with some backlash at its lower end to assist in control of the movement of small flows of cigarettes.

The apparatus also includes a part-cylindrical cowl 32 which extends over the whole of the width of the roller 22 and is mounted so as to be able to move slightly about both a horizontal and a vertical axis at one end of the cowl, each of which lies parallel with the plane of the paper. This cowl 32 has two functions; one of these is to screen the upcoming band 18, as it passes over the roller 22, from the downcoming cigarettes (passing into the stack D); the second function, for which purpose it is designed to be pivotable, is to take up the gap which tipped cigarettes tend to produce at their ends remote from the tips when they are handled in stacks. Thus in the present apparatus, with the cowl 32 being pivotable at one end, tipped cigarettes would be fed in with their tipped ends lying at the end of the cowl remote from the pivot.

Control apparatus is provided to control the speeds of the conveyors 6 and 7 feeding the stacks A and B and to control the position of the flap plate 5 according to the signals received from the detector devices and to control the speeds of the conveyors 6 and 7 according to the signals received from the sensors 13 and 14, so as to maintain a constant orderly flow of cigarettes and in order also, so far as possible, to arrange that the volumes of the cigarettes in the reservoirs A and B remain approximately equal.

In operation, the cigarettes in the stack A are conveyed on the conveyor band 6 to the mouth of the chute 17 where they move downwards in stack formation to the region of the flap plate 5 where the stack B also arrives. At this point some fluidization occurs; that is to say the cigarettes are caused to undergo some movement relative to one another as a result of the combined effects of their downward motion, of the various moving surfaces, and of the interaction of the two stacks. The cigarettes then travel for a short distance in a single stream through the merger zone, after which they may undergo redistribution and move into either the stack C or the stack D. The band 7 and the roller 25 tend to promote fluidization in the region of the throats 34 and 35.

One feature of the construction shown is that with either of the stacks C and D stationary, it is possible for cigarettes moving into the other stack to move across a stationary downwardly inclined surface of cigarettes. This surface will occur either generally between the rollers 11 and 22 if the stack D is stationary, or between rollers 25 and 22 if the stack C is stationary. In either event the whole flow from the stacks A and B (or the single flow if one of these stacks is stationary) can proceed smoothly into the other stack. This feature greatly increases the flexibility of the cigarette-handling system and in particular it can enable production to continue even though one of the reservoirs is emptied or some stoppage has occurred.

If it is desired to use the apparatus on occasion to convey two separated flows, one from A into C and one from B into D, then the flap plate 5 can be provided with or replaced by an extension plate which can be set to form a vertical partition between the two flows, extending vertically down to the cowl 32.

As an alternative, instead of two stacks being delivered from the merger zone 33, the arrangement may be such that only one stack is delivered permanently from the merger zone (eg by the conveyor 18, with the channel to the stack D being closed off). In this case two (or more) packing machines may be fed with cigarettes through vertical chutes extending downwards from the stack delivered by the conveyor 18, for example as described in Molins French Pat. No. 1,509,322.

What 1 claim as my invention as desire to secure by Letters Patent is:

l. A sensor for controlling the feed of cigarettes or other rodlike articles in stack formation on a conveyor and into a downwardly extending chute, comprising a plate pivoted about a substantially horizontal axis upstream of the chute and arranged to rest on the articles so as to swing upwards and downwards about its pivot axis in response to the pressure of the articles beneath it, including means for controlling the conveyor in response to movement of the sensor plate, and guide means cooperating with an edge of said plate in all positions of the plate to prevent articles from rising above the level of said plate, including a top wall situated above and parallel to the conveyor at substantially the same height as the upstream end of the sensor plate to contact and confine the upper surface of the stack of articles on the conveyor as it approaches the chute.

2. A sensor according to claim 1 in which the bottom surface of the plate is convex as viewed in the direction of the articles.

3. A sensor according to claim 1 in which the plate is pivoted about an axis parallel to the articles.

4. A sensor according to claim 3 in which the part of the plate which rests on the articles is downstream of the pivot in relation to movement of the articles.

5. A sensor according to claim 1 in which the sensor plate is pivotally mounted by means of a spindle which forms the input to a rotary speed-regulating mechanism which controls the conveyor speed.

6. A sensor according to claim 1 in which the free end of the sensor intermeshes with a stationary member to prevent the escape of any articles.

7. A sensor for controlling the feed of cigarettes or other rodlike articles in stack formation on a conveyor in relation to which the articles lie transversely, in which the sensor is located above, a downwardly extending chute and has a length substantially the same as the width of said chute, said sensor resting on the articles beneath it, being substantially horizontal but with a convex shape whereby it sinks rapidly into the hollow which forms in the upper surface of the articles above the chute when the flow rate of articles down the chute exceeds that of the articles conveyed to the chute by the conveyor, and including a top wall situated above and parallel to the conveyor at substantially the mean height of the sensor to contact and confine the upper surface of the stack of articles on the conveyor as it approaches the chute.

8. A sensor assembly according to claim 7 including a second conveyor for delivering a second stack of articles from the junction zone.

9. A sensor for controlling the delivery of cigarettes passing in stack formation down a chute from a horizontal conveyor, comprising a sensor plate situated above the chute and pivotally mounted by means of a horizontal spindle lying laterally in relation to movement of the conveyor towards the chute, the spindle being upstream of the chute and being arranged as the input to a rotary speed-regulating mechanism which automatically regulates the rate of delivery of cigarettes by the conveyor, the sensor plate being formed with an underneath surface which is convex as viewed in the direction of the spindle, and including a stationary top wall which lies above the horizontal conveyor at the same height as the pivoted end of said plate and contacts and confines the upper surface of the stack of cigarettes on the conveyor as it approaches the chute.

10. A conveyor system for cigarettes and other rodlike articles, comprising a horizontal conveyor for conveying the articles in stack formation in a predetermined direction; a chute for receiving a stack of articles from the said horizontal conveyor and comprising substantially vertical walls; a sensor plate mounted above the chute in the path of the articles on said horizontal conveyor and having substantially the same length as the width of the chute, the sensor plate having a substantially horizontal mean position and being carried by a pivotally mounted member at one side of the sensor plate whereby the plate can pivot about a horizontal axis lying transversely in relation to the direction of motion of the conveyor; and control means operatlvely connected to the pivotally mounted member which carries the sensor plate so as to move in response to pivotal movement of the sensor plate about its pivot axis, the said control means being arranged to control the movement of the said horizontal conveyor in response to movement of the sensor plate to provide an adequate supply of articles to the chute.

11. A conveyor system according to claim 10 including a stationary wall which intermeshes with the sensor plate to prevent articles from rising above the level of the plate.

12. A conveyor system according to claim 11, in which the said stationary wall intermeshing with the sensor plate comprises a vertical extension of one of the walls of the chute. 

1. A sensor for controlling the feed of cigarettes or other rodlike articles in stack formation on a conveyor and into a downwardly extending chute, comprising a plate pivoted about a substantially horizontal axis upstream of the chute and arranged to rest on the articles so as to swing upwards and downwards about its pivot axis in response to the pressure of the articles beneath it, including means for controlling the conveyor in response to movement of the sensor plate, and guide means cooperating with an edge of said plate in all positions of the plate to prevent articles from rising above the level of said plate, including a top wall situated above and parallel to the conveyor at substantially the same height as the upstream end of the sensor plate to contact and confine the upper surface of the stack of articles on the conveyor as it approaches the chute.
 2. A sensor according to claim 1 in which the bottom surface of the plate is convex as viewed in the direction of the articles.
 3. A sensor according to claim 1 in which the plate is pivoted about an axis parallel to the articles.
 4. A sensor according to claim 3 in which the part of the plate which rests on the articles is downstream of the pivot in relation to movement of the articles.
 5. A sensor according to claim 1 in which the sensor plate is pivotally mounted by means of a spindle which forms the input to a rotary speed-regulating mechanism which controls the conveyor speed.
 6. A sensor according to claim 1 in which the free end of the sensor intermeshes with a stationary member to prevent the escape of any articles.
 7. A sensor for controlling the feed of cigarettes or other rodlike articles in stack formation on a conveyor in relation to which the articles lie transverselY, in which the sensor is located above a downwardly extending chute and has a length substantially the same as the width of said chute, said sensor resting on the articles beneath it, being substantially horizontal but with a convex shape whereby it sinks rapidly into the hollow which forms in the upper surface of the articles above the chute when the flow rate of articles down the chute exceeds that of the articles conveyed to the chute by the conveyor, and including a top wall situated above and parallel to the conveyor at substantially the mean height of the sensor to contact and confine the upper surface of the stack of articles on the conveyor as it approaches the chute.
 8. A sensor assembly according to claim 7, including a second conveyor for delivering a second stack of articles from the junction zone.
 9. A sensor for controlling the delivery of cigarettes passing in stack formation down a chute from a horizontal conveyor, comprising a sensor plate situated above the chute and pivotally mounted by means of a horizontal spindle lying laterally in relation to movement of the conveyor towards the chute, the spindle being upstream of the chute and being arranged as the input to a rotary speed-regulating mechanism which automatically regulates the rate of delivery of cigarettes by the conveyor, the sensor plate being formed with an underneath surface which is convex as viewed in the direction of the spindle, and including a stationary top wall which lies above the horizontal conveyor at the same height as the pivoted end of said plate and contacts and confines the upper surface of the stack of cigarettes on the conveyor as it approaches the chute.
 10. A conveyor system for cigarettes and other rodlike articles, comprising a horizontal conveyor for conveying the articles in stack formation in a predetermined direction; a chute for receiving a stack of articles from the said horizontal conveyor and comprising substantially vertical walls; a sensor plate mounted above the chute in the path of the articles on said horizontal conveyor and having substantially the same length as the width of the chute, the sensor plate having a substantially horizontal mean position and being carried by a pivotally mounted member at one side of the sensor plate whereby the plate can pivot about a horizontal axis lying transversely in relation to the direction of motion of the conveyor; and control means operatively connected to the pivotally mounted member which carries the sensor plate so as to move in response to pivotal movement of the sensor plate about its pivot axis, the said control means being arranged to control the movement of the said horizontal conveyor in response to movement of the sensor plate to provide an adequate supply of articles to the chute.
 11. A conveyor system according to claim 10, including a stationary wall which intermeshes with the sensor plate to prevent articles from rising above the level of the plate.
 12. A conveyor system according to claim 11, in which the said stationary wall intermeshing with the sensor plate comprises a vertical extension of one of the walls of the chute. 